There are a few secret ones, like completing arcade games on the circus looking mission...like pitfall but with super heros as the characters, or pong! Then there are the push people off cliff ones. Pretty fun!

I beat the game a while ago and I didn't get an achievement for beating the game. After you beat it it goes through all of yhe missions and says the things you didnt do that you should have. It'll say because you didnt do this all the mutants die or whatever. So if your just starting it, try and do all of the secondary objectives. Most of the time he'll say you should do this, but its not that important so don't worry about it.

You don't even need the guide to get those achievements, just some patience and a decent memory.

To get 150 questions answered just go through each trivia section and re-answer any questions you got wrong the first time. Complete one trivia section, save before you attempt them, load up your game again and answer with the solutions you just got.

What is the difference between the coop and aracade, because I was playing with another person and when you go into a shield check point it asks you if you want to switch to aracade mode and when you do, you just have 2 super heros. Does that mean when you go thru the game that you will only have 2 heroes to control if there are only 2 of you??

Arcade is basically co-op, only at the end of every section you are given points based on things like how many kills you get, how many shield tokens you pick up, items you break and so on. Whoever gets the most points 'wins' and you carry on with the level.

Just thought i would confirm that 100 Arcade Wins can be done in 2 sittings.

I was doing it on Wrenchworks, saved frequently. Last save was at 44 and then a few after it hung. Reset my console, did 56 more and got it then.

If you want to ammend the Achievement Guide thats cool, as when PerpetualHeaven wrote it he said, "I don’t have this achievement yet and the only people who I know who have it don’t know if you can turn off your console and continue. So please be careful when you do this because if your 360 stalls like mine did (at 40 arcade wins), you might have to restart all over again from 0."

Basically it saves your arcade wins number at your last save, so when you continue from that save you can continue from that number.

I didn't know how to submit this to the guy that wrote the guide on here but I have found out much faster and simpler ways to get the Ultimate Team Alliance Achievement which also includes Team Work and I Have a Friend and Super Hero Team. Also 4000 kills too.

Here is how it is done.Get 3 others online with you or plug in 4 controls. Then play to or load up a save inside Stark Tower. Then all you do is go in and out of Iron Man's lab (behind the waterfall at the back of the main area) and boom achievement unlocked.

Also here is a better way to get costumes unlocked.For this one it is preferable that you have played through the game at least once so you have quite good characters.Play to or load up a save at the very beginning of Mephesto's Realm on Easy difficulty. Go save the game at the SHIELD post and then choose the character you wish to unlock the costume for. After you have chosen jump all the other character over the edge. Then with the character you have chosen go to the part with the infinite spawning gremlin type things (the part where you have to throw them into the lava to lower the platform). Now figure out that characters best spawn camping move, e.g. strong enough to kill quickly but fast enough to do in rapid succession. Then just spawn camp the gremlin things, you should be able to figure out the fastest way of dispatching the enemies which each character and just keep doing that. Health and Energy aren't important because most of the kills will drop more of each. So once you have unlocked the costume you are going for then hit start and load back up at the SHIELD post. You will still have the costume and you can now repeat with a new character.Note: After each costume you unlock remember to save over the save you load from otherwise all the costumes will disappear when you turn off.

This is also the fastest way to get 4000 kills too, and a high level Ice Shards attack from Iceman is extremely fast way to kill the enemies.Here is a link to a video of me demonstrating just how fast and easy this method is. Sorry about the quality but all I had on hand was my camera phone's video recorder.